Page ! 1BMB 401 US 2015 Exam IALOGARITHMS THAT MIGHT BE USEFUL ANTILOGS THAT MAY BE USEFUL log 0.01 = -2log 0.1 = -1log 1 = 0log 2 = 0.30log 3 = 0.48log 4 = 0.60log 5 = 0.70log 6 = 0.78log 7 = 0.84log 8 = 0.90log 9 = 0.95log 10 = 1.0log 100 = 2.0anti log 1 = 10anti log 2 = 100anti log 3 = 1000anti log -1 = 1/10anti log -2 = 1/100anti log -3 = 1/ 1000Page ! 2BMB 401 US 2015 Exam IA !A Ala Alanine M Met Methionine C Cys Cysteine N Asn Asparagine D Asp Aspartate P Pro Proline E Glu Glutamate Q Gln Glutamine F Phe Phenylalanine R Arg Arginine G Gly Glycine S Ser Serine H His Histidine T Thr Threonine I Ile Isoleucine V Val Valine K Lys Lysine W Trp Tryptophan L Leu Leucine Y Tyr Tyrosine Unit Conversion nM = 10-9 molar, µM=10-6 molar, mM= 10-3 molarAmino Acid 1- and 3-letter CodespKas of Amino Acid Functional GroupsPage ! 3BMB 401 US 2015 Exam IA1)Please choose the true statement: a) Proteins, nucleic acids, vitamins and lipids represent the 4 classes of macromolecules. b) For an aqueous solution of weak acid at a pH equal to the pKa of a weak acid, [acid] = [conjugate base]. c) The pI of a peptide is the pH at which each amino acid in that peptide is neutral in charge. d) All the above are true. e) Only b and c are true. 2)The enzyme used in your experiment has an optimal of pH of 8.3. You must choose a buffer to use during your experiment. Which of the buffers below will you not use? a) Buffer A: pKa = 7.8 b) Buffer B: pKa1 = 4.8, pKa2 = 8.8 c) Buffer C: pKa1 = 3.8, pKa2 = 7.8 d) Buffer D: pKa1 = 2.8, pKa2 =5.8 3)For the question above, you excluded one buffer. Are the remaining buffers equally as good at buffering at a pH of 8.3? a) Yes, b) No, only A and C are the best. c) No, only B is best. d) No, only C is best. e) No, only D is best. 4)Please select the true statement: a) The psi and phi angles in a peptide refer to the angles of rotation about the alpha carbon and not the peptide bond. b) The psi and phi angles in a peptide refer to the angles of rotation about the peptide bond and not the alpha carbon. c) Psi and phi angles are said to have values between 0 and 360. d) There is no true statement here. 5)Please select the true statement: a) One definition of an acid and a base is that an acid is a proton acceptor, and a base is a proton donor. b) CO2 combines with H2O to form carbonic acid, which deprotonates to form bicarbonate at physiologic pH. c) The primary blood buffer is the phosphate buffering system. d) There are no true statements here. 6)Please solve for pH when pKa = 7.2, and the molar concentration of dihydrogen phosphate, H2PO4– = 10 mM and the molar hydrogen of hydrogen phosphate, HPO42– = 100 µM. pH = 8.2, b. 9.2, c. 6.2, d. 5.2, e. The correct value for pH is not here. 7)Please select the true statement: a) Van der Waals attractive forces become stronger as two atoms or groups approach each other, until they reach the limit of their Van der Waals radii. b) When ∆G for a reaction is greater than zero, the reaction will proceed in the forward direction. c) HCl and KOH dissociate incompletely in aqueous solution, such that the concentrations of protonated and deprotonated acid is dependent on the pH of the solution. d) When ∆G for a reaction is zero, the reaction proceeds in the reverse direction. 8)The 6 coordination sites of the iron in heme are the 4 pyrrole nitrogens, & distal and proximal histidines. True False 9)The chiral amino acids found in biosystems are predominantly L-stereoisomers. True False 10)The strength of ionic bonds is directly proportional to the dielectric constant of the solvent. True FalsePage ! 4BMB 401 US 2015 Exam IA11)Please select the *FALSE* statement: a) Alpha helices in most proteins are right-handed. b) The total entropy of a system must increase for a reaction to be favorable. c) A beta-turn is a secondary structural element representing a sharp turn that changes the direction of a peptide strand. d) The oxidation state of methemoglobin is 3+. 12)Please select the *FALSE* statement: a) Glycogen is a storage form of glucose polymer that is found in animal tissues. b) Hydrogen bonding is greater in glycogen and starch than it is in cellulose and chitin. c) The bonds linking sugars together to form carbohydrate polymers are called glycosidic bonds. d) Cellulose and starch are both glucose polymers. e) Glycogen is more highly branched than starch. 13)Please select the true statement: a) Interactions between amino acid side chains determine whether any two given amino acids residues will form a peptide bond. b) Valine and methionine are hydrophobic, branched chain amino acids. c) Tryptophan, tyrosine, and phenylalanine are aromatic amino acids d) There are no true answers here. 14)Please choose the True statement regarding Protein A, which is a trimeric membrane protein that is positioned completely in the membrane: a) Glutamine will be more likely to be found on the exterior than in the interior of the protein . b) This protein will have primary, secondary, tertiary, and quaternary structure. c) This protein will have primary, secondary, tertiary structure, but will not have quaternary structure. d) All the above are true. e) All but c are true. 15)Please select the true statement: a) The myoglobin and hemoglobin of humans are orthologs b) Leghemoglobin and human myoglobin are orthologs. c) The distal histidine is a coordination site for iron in the heme prosthetic group in myoglobin and hemoglobin. d) All the above are true e) Only b and c are true 16)Which of the following is true? a) The affinity of the small molecule 2,3-BPG for hemoglobin is higher in acidic conditions. b) The affinity of the small molecule 2,3-BPG for hemoglobin is lower in metabolically active tissues. c) The small molecule 2,3-BPG has a higher affinity for HbA than HbF. d) The small molecule 2,3-BPG increases the affinity of hemoglobin for oxygen. e) All but d are true. f) Only a and c are true. 17)During the process of transcription The RNA template is read in the 5´-3´direction. True False 18)In regard to alpha helices, hydrogen bonds that stabilize this structure are parallel to the axis of the helix and are formed between amino acids that are 3 to 4 residues apart. True
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